Glycerol is the most widely used plasticizer for the biopolymer chitosan. However, there remains a lack of understanding of the molecular-level interactions between chitosan and glycerol. Here, we describe an in-depth spectroscopic study of the intermolecular interactions between the monomeric repeating unit of chitosan, glucosamine, and the plasticizer glycerol. Infrared and nuclear magnetic resonance spectroscopy were used to probe glucosamine assembly at high and low concentrations to establish diagnostic signals for intra- and intermolecular glucosamine interactions. Systematic addition of glycerol was found to disrupt intramolecular glucosamine hydrogen bonds and promote glucosamine self-assembly. Furthermore, we observed a significant preference for glycerol binding to the amine functionality of glucosamine. These findings indicate that the plasticization of chitosan with glycerol requires a specific binding motif and likely occurs via the gel theory mechanism.

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An overview of the research capabilities and the future plans on the MA-class National Spherical Torus Experiment (NSTX) at Princeton is presented. NSTX research is exploring the scientific benefits of modifying the field line structure from that in more conventional aspect ratio devices, such as the tokamak. The relevant scientific issues pursued on NSTX include energy confinement, MHD stability at high β, non-inductive sustainment, solenoid-free start-up, and power and particle handling. In support of the NSTX research goal, research tools are being developed by the NSTX team. In the context of the fusion energy development path being formulated in the US, an ST-based Component Test Facility (CTF) and, ultimately a high β Demo device based on the ST, are being considered. For these, it is essential to develop high performance (high β and high confinement), steady-state (non-inductively driven) ST operational scenarios and an efficient solenoid-free start-up concept. We will also briefly describe the Next-Step-ST (NSST) device being designed to address these issues in fusion-relevant plasma conditions.

The American Meteorological Society held its Eighth Symposium on Education in conjunction with the 79th Annual Meeting in Dallas, Texas. The theme of this year's symposium was "Enhancing Public Awareness of Weather and Climate Prediction." Forty oral presentations and 58 poster presentations summarized a variety of educational programs or examined educational issues for both the precollege and university levels. There was also a joint session with the 11th Conference on Applied Climatology and a special session on uses of educational technology for effective teaching and learning. Over 200 people representing a wide spectrum of the Society attended one or more of the sessions in this two-day conference. The program for the Eighth Symposium on Education can be viewed in the October 1998 issue of the Bulletin.

Project ATMOSPHERE, the K–12 educational program of the American Meteorological Society, has been involved in teacher enhancement for four years. Summer workshops for teachers have been a primary component of the AMS K–12 educational initiatives since its inception. During the summer of 1994, Project ATMOSPHERE conducted four workshops: two of the workshops were for teachers in the Atmospheric Education Resource Agent program; another was for K–12 teachers, including one teacher each from Canada and Australia; and the fourth was for faculty members at community colleges or four-year undergraduate institutions. These workshops provide teachers at all levels with instruction on a variety of atmospheric topics, an introduction to the operational and research activities of the meteorological community, and exposure to atmospheric scientists and their facilities. Such workshops provide enriching experiences for educators who teach about weather and climate topics in their science classrooms.